During his tenure in Kazan, Abp. Hilarion actively supported theological education. He transformed the Slavonic-Latin school, that was founded in 1723 to educate the children of clergy, into a seminary and moved it to facilities at the Zilantov Monastery, now the Holy Dormition Convent on Zilant Hill. Later, the Kazan Seminary was moved into its own building that Abp. Hilarion had built.

In 1735, the Holy Synod transferred Abp. Hilarion to the Eparchy of Chernigov from which position he retired in 1742. Abp. Hilarion reposed in 1750 and was buried in Tver.